On Thu, Mar 29, 2007 at 02:16:54PM -0700, Linus Torvalds wrote:> > > On Thu, 29 Mar 2007, Andi Kleen wrote:> > > > Here's a patch. I don't have a system with C1E, so i only tested that> > the apic timer still works on a older AMD box.> > I think this looks better than what we have now, but it would look even > better if the core CPUID stuff was in arch/i386/kernel/cpu/amd.c, and we > simply had X86_FEATURE_BROKEN_C1_LAPIC etc..

Please don't, this would break the interface logically.X86_FEATURE_xxx usually denotes a *feature*, not a "feature"(Micro$oft speak for "bug" ;).IOW most flags express a positive attribute, not a negative one.An exception to this probably is X86_FEATURE_FXSAVE_LEAK andX86_FEATURE_CMP_LEGACY, but all others seem to be positive, so we mightwant to enforce this rule.

Thus, how about e.g. X86_FEATURE_LAPIC_C1_OK?Or is this less precise from a "C1 working ok" detection point of view?(i.e. we'd just assume by default that most machines are ok except the oneswhere we have issue detection code for, which might be too fuzzy)